Until I developed peripheral neuropathy and had fasciculations myself, I never knew anyone else who had them or who talked about it. Fasciculations talked about here involve a duration over a period of time with relative frequency, with no other cause such as over exertion. It doesnt refer to a twitch here or there.
For people with peripheral neuropathy it signals that there is involvement of the motor nerves which are affecting the muscles.

I did work where there were periods of time of extreme strenuous exertion and high stress and never had them before my feet started going numb. I never heard of anyone at work having them either. I dont think they are all that common.